[1]刘怀,沈捷,费树岷.用双优先级算法调度控制系统的实时周期性任务[J].东南大学学报(自然科学版),2003,33(2):190-193.[doi:10.3969/j.issn.1001-0505.2003.02.018]
 Liu Huai,Shen Jie,Fei Shumin.Scheduling real-time periodic task of control system with dual priority algorithm[J].Journal of Southeast University (Natural Science Edition),2003,33(2):190-193.[doi:10.3969/j.issn.1001-0505.2003.02.018]
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用双优先级算法调度控制系统的实时周期性任务()
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《东南大学学报(自然科学版)》[ISSN:1001-0505/CN:32-1178/N]

卷:
33
期数:
2003年第2期
页码:
190-193
栏目:
计算机科学与工程
出版日期:
2003-03-20

文章信息/Info

Title:
Scheduling real-time periodic task of control system with dual priority algorithm
作者:
刘怀12 沈捷1 费树岷1
1 东南大学自动化研究所, 南京 210096; 2 南京师范大学电气电子工程学院,南京 210042
Author(s):
Liu Huai12 Shen Jie1 Fei Shumin1
1 Research Institute of Automation, Southeast University, Nanjing 210096, China
2 School of Electrical and Electronic Engineering, Nanjing Normal University, Nanjing 210042, China
关键词:
双优先级 周期性任务 软实时任务 强实时任务
Keywords:
dual priority periodic task soft real-time task hard real-time task
分类号:
TP316
DOI:
10.3969/j.issn.1001-0505.2003.02.018
摘要:
根据控制系统中存在强实时周期任务和软实时周期任务的特点,采用双优先级算法进行任务调度.该算法将优先级带宽分为3部分:高带优先级、中带优先级和低带优先级.强实时任务实例到达后先将其优先级设置在低带,经过一段时间若还没有完成,则将其优先级提升到高带,软实时任务的优先级设置在中带中,从而控制任务的执行.文章研究了强实时任务优先级提升时间的存在性,给出了求取优化的优先级提升时间的算法.在软实时任务满足一定丢失率(0≤βsi<1)的条件下分析任务集的可调度性,模拟结果表明了算法的有效性.
Abstract:
Since the real-time task sets in control system consist of hard real-time periodic tasks and soft real-time period tasks, the dual priority algorithm is adopted for scheduling these tasks. The algorithm divides priority band into three parts, i.e. high priority band, middle priority band and low priority band. The priority of hard real-time task is set in low priority when its instance arrives and it is promoted into high priority band after a period of time. The priority of soft real-time task is set in middle priority band. The existence of the priority promotion time of hard real-time task is investigated. The method for computing the optimal priority promotion time of hard real-time task is presented. Under the condition that the lost ratio of the soft real-time task’s instances βsis is in certain value (0≤βsi<s1), the schedulability of tasks is analyzed. The result of simulation shows that the scheduling algorithm is effective.

参考文献/References:

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备注/Memo

备注/Memo:
基金项目: 国家攀登计划资助项目(970211017)、国家自然科学基金资助项目(69934010).
作者简介: 刘怀(1971—),男,博士后,smfei@seu.edu.cn; 费树岷(联系人),男,教授,博士生导师.
更新日期/Last Update: 2003-03-20